The Invention Relates to Endoscopes.
Surgical procedures for treating incompetent perforating veins and for harvesting saphenous veins generally require long incisions to be made along the leg of the patient.
Perforating veins run substantially perpendicularly through layers of subcutaneous fat and muscle fascia (i.e., the fibrous layer attached to underlying softer tissue) into the muscle to connect the deep and superficial venous systems. When the perforating veins become diseased (e.g., varicose), it may be necessary to surgically remove portions of the vein, or strip out the entire vein. In milder cases, merely tying off (ligate) the veins to relieve pressure may suffice.
One conventional approach for ablating such perforating veins in the leg is to make a relatively long incision extending from the knee down to below the ankle. However, patients having incompetent perforating veins (particularly the elderly) may suffer from chronic venous insufficiency (CVI), a condition in which the skin becomes ulcerated and often infected. Incisions made through skin in this condition have a relatively high wound complication rate. At best, patient recovery is significantly increased and, in some cases, a new, morbid wound is created.
Saphenous vein harvesting is typically performed in conjunction with coronary (heart) or peripheral artery bypass. Under endoscopic visualization, the saphenous vein is harvested from the leg and used to bypass a clogged artery in the heart or leg. In conventional approaches for removing the saphenous vein, a single long incision or several separate and spaced incisions are made along the length of the leg. The vein is then freed by severing and ligating the branches of the vein, after which the vein is removed from the patient. The single long incision or series of spaced incisions is then closed using, for example, suture or stapes.
A new approach, known as subfascial endoscopic perforator surgery (SEPS), has recently developed as an alternative procedure for performing perforator ligation. In general, the SEPS procedure allows a working instrument to be introduced through a small incision and, with the aid of an endoscope, guided below the fascia to the surgical work area. This is particularly advantageous for patients suffering from chronic venous insufficiency since the SEPS approach allows incisions to be made in healthy tissue remote from the morbid tissue; one incision is generally required for the working instrument, another for the endoscope used to visualize the procedure. Thus, the SEPS approach reduces wound complications often associated with procedures involving long incisions through compromised tissue.